I am trying to view attribute data for a SRTM GeoTIFF in QGIS, but for some reason I can't view the data.
You can access the attribute table if the pixel values are in integer type because opening attribute table of float type raster is not possible. If you have ArcGIS, you can open the attribute table after converting the float type raster into integer type, but unfortunately, this cannot be done in QGIS even if you converted your raster to integer type. Check Accessing raster attribute table in QGIS? as there was a request to add this function in QGIS, but until now it is not implemented.